bagnall



(No Model.) 2 SheetsSheet 1. h E. J. BAGNALL & G. ARNOLD.

ELECTRIC ARC LAMPJ Patented Jan. 28, 1896.

No Model.) 2 Sheets-.Sheet 2. E. J. BAGNALL 8v G. ARNOLD.

ELECTRIC ARC LAMP.

W31 asses AN DREW BVGRAMAM. PHDTOUTNO. WASMI NGTUMDYC UNITED STATESPATENT OFFICE.

ERNEST J. BAGNALL AND GEORGE ARNOLD, OF CLEVELAND, OHIO, ASSIGN- ORS TOTHE ADAMS-BAGNALL ELECTRIC COMPANY, OF SAME PLACE.

ELECTRlC-ARC LAM P.

SPECIFICATION forming part of Letters Patent No. 553,637, dated January28, 1896.

Application filed October 2, 1896.

T 0 all whom it may concern:

Be it known that we, ERNEST J. BAGNALL and GEORGE ARNOLD, of Cleveland,in the county of Ouyahoga and State of Ohio, have invented certain newand useful Improvements in Are Lamps; and we do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

Our invention relates to an improvement in electric-arc lamps, and moreparticularly to such as are adapted to be operated with alternatingelectric currents.

In alternating-current are lamps as heretofore constructed the carbonsare arranged in series with the separating and feeding coil and arenormally in contact when no current is passing through the lamp. Thecoil is provided with a movable core or armature, to which the clutchdevices or other mechanical feeding mechanism is attached. It is obviousthat when current first enters the lamp it will flow through the coiland carbons. The carbons being normally in contact, the resistance tothe current will be at the minimum, and consequently a heavy currentwill flow through the coil. This heavy current actuates the magnetviolently, giving it such power that it pulls the carbons apart sosuddenly as to rupture the arc. The strength of the magnet will, ofcourse, be destroyed when the are is thus ruptured and the carbons willfall together again, closing a circuit of low resistance through thecoil and causing the above operation to be repeated. Thus a violent andannoying chattering takes place until the carbon points shall havebecome sufficiently heated so that an arc can be formed and maintainedbetween them.

It is the object of our invention to provide means whereby to preventthe repeated separations of the carbons, rupturing of the arc, andconsequent violent chattering in an alternating-current arc lamp.

A further object is to provide means for causing the carbons to be sodisposed for a brief period before the normal arc is struck as to form avery small are between them, whereby to raise the temperature of the carSerial No. 56,454. (N0 model.)

bon points to a sufficient degree of heat to cause them to throw off aproper amount of volatilized carbon to maintain the normal are.

WVith these objects in View the invention consists in the combination,with the separating-magnet and carbons of an electric-arc lamp, ofarc-starting devices constructed and arranged to cause the carbon pointsto be sufficiently heated prior to the formation of the normal arc toinsure the maintenance of the normal are when formed.

The invenion also consists in the combination, with theseparating-magnet and carbons of an arc lamp, of arc-starting devicesconstructed and arranged to cause the carbons to be slightly separatedfor a short period before they are separated sufficiently to form thenormal are.

The invention also consists in the combination, with theseparating-magnet and carbons of an arc lamp, of arc-starting devicesconstructed and arranged to retard the separation of the carbons afterthe current enters the lamp and the carbons have begun to separate; andthe invention further consists in certain novel features of constructionand combinations and arrangements of parts, as hereinafter set forth,and pointed out in the claims.

In the accompanying drawings, Figure 1 is a viewshowing portions of anarc lamp with the parts in normal positions when no current is passingthrough the lamp. Fig. 2 is a similar view showing the positions of theparts when the current enters the lamp and before the normal arc isformed. Fig. 3 is a similar view showing the positions of the partsafter the normal archas'been formed. Fig. 4 is a view at right angles toFigs. 1, 2, and

A represents a solenoid which can be supported in the lamp-casin g inany suitable manner and preferably disposed in a vertical position, sothat its core A will project into a frame B arranged in a fixed positionimme diately below the solenoid. The frame B is made with a lateral arm1, having a boss 2, with which one end of a lever 3 is pivotallyconnected, said lever being bent at at and made to project within theframe B immediately under the core A of the solenoid, to

which core the lever is pivotally connected at a point between the endsof the latter. A clutch-rod 5 is pivotally connected to the lever 3 at apoint in proximity to the pivotal point of the latter with the bars 2.The rod 5 depends from its connection with the lever 3 and at its lowerend is connected with a clutch o of any preferred form of construction,or a clutch-blade 7, said rod 5 preferably being made in two partsconnected together by means of a turnbuckle 8, by which latter thelengthof the rod can be adjusted. The holder 0 for the upper carbon isconnected with the clutch-blade 7 and the lower carbon 11 is carried byany suitable devices. (Not shown.)

The lower half of the frame 13 is made thicker than the upper portionand split to form arms 12 13, disposed parallel with the arms 1 c 15 ofthe frame. The arms 12 ll-are made with screw-threaded recesses whichconstitute bearings for a ho1'Mentally-disposed screw 115. A screw 17 ismounted in a simi lar manner between the arms 13 15 and slightly above aline passing through the screw 10. A lever 18 is disposed within theframe B and made with a V-shaped recess 24, in which the conical end 20'of the screw 17 has a bearing, said conical end 26 thus forming the endof the lever. Opposite the recess 21 another V-shaped recess 25 is madein the lever 18 for the reception of a conical head 27, which is looselyconnected at one end of a rod 28. A similar head 20 is loosely connectedto the other end of the rod 28 and has a bearingin the inner end of thescrew 11'. A spring 30 encircles the rod 28 and bears at its respectiveends against the heads 27 29. The lever 18 is prevented from escape fromits bearings by means of disks or nuts 21. The lever 18 is made with anupwardly-extemling curved arm 19, which terminates at its lower end in aflat seat 20 to one side of the fulcrum of the lever, and with thiscurved arm and seat the free end of the lever 3 is adapted to engage ina manner hereinafter more fully explained. The short arm of the lever 18projects downwardly and slightly laterally from the pivotal point of thelever and constitutes a foot 22, adapted, when the parts are in theirnormal positions, (with no current passing through the lamp,) to engagean adjustable stop 23, as shown in Fig. 1.

From this construction and arrangement it will be seen that when theparts are in their normal positions, with no current passing through thelamp, the axis of the spring 30 will be out of line with the axis of thescrew 17 and below the fulcrum of lever 18, so that the force of saidspring will be exerted 011 said lever to cause the foot 22 to bearagainst the adjustable stop 23. NVhcn the parts are in this position,the curved arm 19 of lever 18 will project toward the core A of thesolenoid, the said core will be in its lowest position, and the free endof the lever 3 will rest on the seat 20 of lever 18, as shown in Fig. 1.It is evident that when the core of the solenoid rises, carrying thelever 3 with it, the engagement of the free end of said lever with thecurved arm 19 of lever 18 will cause the latter to turn on its fulcrum,and that when the lever 18 has been moved to a sufficient extent tocause the head 27 at the end of the spring 30 to pass above the fulcrumof said lever and the axis of the screw 17 said spring will exert apressure on the lever 18 to cause the arm 19 to complete its rearwardmovement, pass out of line with the free end of the lever 33 and restagainst an :uljustable stop 31. The stop 31 should be so adjusted thatwhen the curved arm 1.2) is .resting against it the free end of saidcurved arm will be just out of line with the free end of the lever 33.\Vhen the core of the solenoid moves down, (as when the lamp is cut inand out of circuit and the solenoid de-encrgized,) the free end of thelever B will pass the free end of the curved arm 1.) and strike the seat20, thus causing the lever 18 to turn sul'liciently to bring the head 27on spring 30 to pass below the fulcrum of the lcver18, when said springwill cause said lever 18 to return to its normal position, as shown inFig. 1. The above description explains the mechanical operation of ourin'iprovements. Their electrical opera tion and importance in thesuccessful operation of an arc lamp for use with an alternatingelectrical current will next be explained.

As above mentioned, one of the most objectionable features in theoperation. of an arc lamp with an alternating current is the annoyingchattering caused when the lamp is started, and this chattering islargely due to the repeated breaking and making of the circuit betweenthe carbons during the time the points of the carbons are becomingsuiiicicntly heated to insure the maintenai'ice of the normal are. It isknown that before the normal arc can be maintained when an alternatingcurrent is employed the carbon points must be suificiently heated tothrow off a certain amount of volatilized carbon. In alternating-current are lamps the separating solenoid or magnet is included inseries in a normallyclosed circuit with the carbons, so that when thecurrent first enters the lamp the resistance is so low that a heavycurrent passes through the solenoid ormagnet and causes it tobecome sostrong as to violently separate the carbons to their full extent for anormal are and before erations, with the consequent annoying chatter,will continue until the temperature of the points of the carbons shallhave reached such a degree as will cause them to throw off sufficientvolatilized carbon to insure the main- IIO tenance of the normal arc. Bymeans of my improvements I avoid these continuous violent separations ofthe carbons and consequent breaking of the circuit with accompanyin gchatter, an d this result I accomplish by causing a small preliminaryarc to be formed and maintained for a suflicient length of time toproperly heat the carbon points to insure the maintenance of thesubsequentlyformed normal arc. The action of. the parts in theperformance of these functions is as follows:

The parts, when no current is passing through the lamp, assume thepositions shown in Fig. 1, with the carbons in contact with each other.Current being now made to pass through the lamp, the coil or solenoidwill be energized and its core will begin to rise, causing the clutch togrip the clutch-blade and begin to separate the carbons. The core A willrise only a very short distance, however,when its further ascent will bearrested by the engagement of the lever 3 with the curved arm 19 oflever 18; but the carbons have been slightly separated (see Fig. 2)sufficiently to permit the formation of a small are between them. Thecore continues to move upwardly against the resistance offered by thespring 30 and maintain the small are for a sufficient length of time topermit the carbon points to become properly heated to maintain a normalare, at which time the head 27 at the end of spring 30 will have movedpast a line common to the axis of the screw 17 and above the fulcrum oflever 18, whereby to cause the lever 18 to complete its movement, Fig.3, and set free the lever 3 and core A, when the latter will completeits upward movement within the coil A and effect a separation of thecarbons sufficient to form a normal arc which will be maintained.Sufficient range of movement of the lever 3, without engaging the lever18,will be permitted to allow a proper feeding of the carbons; but whenthe lamp is cut out of circuit the core will drop and engage the seat 20of lever 18, causing said lever to assume its normal position, Fig. 1,as above explained, ready to be operated when the lamp is again started.

Various slight changes might be made in the details of construction ofour invention without departing from the spirit thereof or limiting itsscope, and hence we do not wish to limit ourselves to the precisedetails herein set forth; but,

Having fully described our invention, what we claim as new, and desireto secure by'Letters Patent, is-

1. The combination with the separating magnet and the carbons of an arclamp, of are starting devices so constructed and arranged as to causethe carbons to be sufficiently heated before the formation of the normalarc to insure the maintenance of said normal arc when formed,substantially as set forth.

2. The combination with the separating magnet and carbons of an arclamp, of are starting devices constructed and arranged to cause thecarbons to be slightly separated for a short period before they areseparated sufficiently to form the normal arc, substantially as setforth.

3. The combination with the separating magnet and carbons of an arclamp, of are starting devices constructed and arranged to form a smallare between the carbons before the formation of the normal are,substantially as set forth.

a, The combination with the carbons of an arc lamp, and a separatingmagnet, of are starting devices intermediate of said carbons and theseparating magnet so constructed and arranged that when current entersthe lamp the carbons will be first slightly separated to form a smallare for heating the carbon points and then separate the carbons to formthe normal arc, substantially as set forth.

5. The combination with the separating magnet and carbons of an arclamp, of are starting devices constructed and arranged to retard theformation of a normal are after the carbons have begun to separate,substantially as set forth.

(5. 111 an arc lamp, the combination with the carbons, a magnet and alever connected with said carbons and the armature of the magnet ofdevices adapted to engage the lever and retard the formation of a normalare after the carbons begin to separate, substantiallyas set forth.

7. In an arc lamp, the combination with a separating magnet, and thecarbons, of a pivoted lever connected with the armature of said magnet,a connection .between said lever and the carbons, a curved levernormally disposed in the path of the first-mentioned lever and a springbearing against said curved lever and adapted to control the movementsof the same, substantially as and for the purpose set forth.

8. In an arc lamp, the combination with the carbons and a magnet inseries with said carbons, of a pivoted lever connected with the armatureof said magnet, a connection between said lever and carbons and a springactuated retarding device adapted to be engaged by said lever and torelease saidlever, successively, substantially as set forth.

9. In an arc lamp the combination with a magnet and the carbons of alever connected with the armature of said magnet and with the carbons,of a spring actuated retarding lever adapted to be engaged by said firstmentioned lever and adjustable stops constructed and adapted to limitthe movements of said retarding lever, substantially as set forth.

10. In an arc lamp, the combination with a magnet, and the carbons of alever connected with the armature of said magnet and with the carbons, aretarding lever to be engaged by the first mentioned lever, and a springcon structed and adapted to bear against said retarding lever, andretain it in the position to which it may be moved, substantially as setforth.

11.. In an arc lamp, the combination with a magnet, and the carbons, ofa lever connected with the armature of the magnet and with the carbons,a retarding lever adapted to be engaged by said first-mentioned leverand a spring bearing against said retarding lever normally at one sideof its fulcrum, substantially as set forth.

12. In an arc lamp, the combination with a separating magnet, and thecarbons of a pivoted lever connected with the carbons and with thearmature of the magnet, a retarding lever adapted to be engaged by thefirst-mentioned lever, a pivotal bearing for said retarding lever, aspring adapted to normally bear against said retarding lever at one sideof its fulcrum, a foot on the retarding lever and a stop to be engagedby said foot, substantially as set forth.

13. In an arc lamp, the combination with a separating magnet, and thecarbons, of a pivoted lever connected with the armature of the magnetand with the carbons, a retarding lever, adapted to be engaged by saidlll.'Sll11lO1ltioned lover, a screw forming a pivotal bearing for saidlever, a spring having a bearing at one end against the frame of thelamp and a head at the other end of said springhaving a bearing in arecess in the retarding lever at one side of its fulcrum, substantiallyas set forth.

ll. In an arc lamp, the combination with a separating magnet and thecarbons, of a pivoted leverconnected with the arlnatnre ol' the magnetand with the carbons, screws in diametrically opposite arms of the lampframe, said springs being ontof line with each other, a retarding leverto be engaged by the first mentioned lever and having one of said screwsfor its fulcrum, a spring, and heads at the ends of said spring, one ofsaid heads having a bearing in one of said screws and the other headhaving a bearing against the retarding lever normally at one side of thefulcrum thereof, substantially as set forth.

15. In an arc lamp, the combination with a separatii'ig magnet and thecarbons, of apivoted lever connected with the armature ol' the magnetand with the carbons, a retarding lever having a pivotal bearing in thelamp frame, said retarding lever having a curved arm to be engaged bythe first mentioned le ver, a seat on the retarding lever to one side ofits fulcrum to be engaged by the first-mentioned lever and a springadapted to bear against the retarding lever normally at one side of itsfulcrum, substantially as set forth.

In testimony whereof We have signed this specification in the presenceof two subscribin witnesses.

ERNEST J. BAGNALI). GEORG l ARNO Ll \Yitnesses:

11;. F. \VHITMAN, ED T. Ilomms.

